Is it dangerous to snort Ritalin and Adderall?

Recently I have started snorting Ritalin and Adderall (not at the same time though). I have found that the effects closely resemble that of snorting cocaine, but are not quite as intense. I really like doing this, because it's much cheaper than buying coke. However, I was wondering exactly how dangerous this might be, if even at all, considering it's a prescribed drug and I never snort more than the average dose that you would take orally. If you could tell me what the danger in doing this is and what I might possibly be doing to my body, that would be great.


How long should I wait to use Viagra after using poppers?

I know that it is extremely dangerous to mix viagra (or other ED drugs) and poppers (amyl nitrate), and that one should wait for 24 hours after using viagra (to let it get out of your system) before using poppers. My question is what is the waiting period after using poppers before it is safe to use viagra? In other words, how long before the physiological effects of poppers wear off?